Pneumatic clutch.



J. SPRINGER.

Patented May 30, 1916.

2 SHEETS-SHEET I.

V Fig- 5 P y WITNESSES. I I l/Vl/EIVTUR I v 7 Joiz z Sprz'ayer- A T TORNEY J. SPRINGER.

PNEUMATIC CLUTCH. APPLICATION FILED JULY 23, 1914. I

- Patented May 30,1916.

2 SHEETSISHEET 2.

. WITNESSES} v V INVENTOR W g j Jb/zn Springer 4 TTOR/VE Y JOHNSPRINGER, 015 DETROIT, MICHIGAN.

PNEUMATIC oLU'reH.

Specification of Letters Patent.

' Patented May 30, 19-16.

Application filed July 23,1914. Serial No. 852,721.

0 all whom it may concern Be it known that I, JOHN SPRInGER, a citizenof the United States of America, re-

siding at Detroit, in the county of Wayne and State of Michigan, haveinvented: certain new and useful Improvements in Pneumatic Clutches, ofwhich the following is a specification, reference being had therein tothe accompanying drawings.

The invention relates to pneumatic clutches of that type involving anair compressor arranged between the drive and driven members, and astorage for the compressed air, the power being transmitted through themedium of the compressed air which is raised to a pressure balancing theload.

The present invention comprises various features by which certaindefects of con'- structions heretofore used are overcome, and including,first, the. reduction of the clearance volume or storage, so that theclutch. will pick up its load more rapidly; second, the placingof thefull accumulated pressure upon each piston at the beginning of itseffective stroke; third, the more perfect balancing of parts, wherebythe operation is not affected by centrifugal action;

and fourth, the improvement in various details of construction as morefully here-- inafter set forth. v

In the drawings: Figure 1 is a sectional elevation parallel to the planeof rotation of the clutch; Fig. 2 is a section in. the plane of theaxis; Fig. 3 is a sectional elevation showing the operation of the valvemechanism; and Fig. 4 is a plan view of one of the cylinder heads. Fig.5 is a detail view showing how in my invention connecting rods areengaged in pairs with the crank of the engine shaft.

A is the drive shaft, such for instance as the crank shaft of an engine.

B is a rotary head mounted upon this shaft and constituting thefly-wheel therefor. This head is provided with a plurality ofradially-extending cylinders C in each of which is arranged a piston D.a

E is the driven shaft which is axially alined with the shaft A and isprovided with a crank F arranged within a central recess G in the headB. The crank F is lows: One difliculty which has been heretoforeexperienced is the rapid wear of the crank bearings. This is due to thefact that these bearings are not easily lubricated, for

the centrifugal action tends to throw off the lubricant, resulting inthe seizure of the relatively moving parts. The substitution of rollerbearings for parallel bearings will avoid this difficulty, but anotherdifliculty is involved to properly mount said bearings within the spacelimits. With my im ,p'roved construction, I first arrange the cylindersin pairs, which are in the same plane and diametrically -opposite eachother. The pitman rods for these cylinders are therefore in the sameplane and are provided with segmental heads H, which engageoppositesides of the ball bearing I, being cut away to provide clearancesuflicient for the relative angular movement of the rods. The rods ofeach pair are then connected to each other by rings J which embracelaterally extending segmental flanges K. The several pairs of opposedcylinders are arranged ,in slightly different planes, so'that their rodsmay be arranged.

adjacent to each other and engage adjacent portions of the crank F. Thusthe ball bearings I which are directly in the plane of the pitman 'rodsreceive the maximum stress, which is the compression stress and bothreduce the friction and prevent wear even where the lubrication isslight. On the other hand, the tension stress is taken care of by theengagement between the rings J and flangesK, while the whole structureis one which permits of mounting upon a crank pin of comparatively shortlength. r

A relative movement of the drive shaft A and driven shaft E will causethe reciprocati'on'of the pistons in the cylinders, which movement willbe resisted by the compression of the contained volume of air. To giveflexibility, a clearance volume is provided for receiving the aircompressed in each cylinder, but this volume is so restricted that thepressure will rapidly rise to balance the load. I preferably form thisclearance volume or storage by cored chambers formed in the head B, and,as shown, annular chambers L and L are arranged around the crank chamberwithin said head and are connected with longitudinal'passages M in thewalls of each cylinder. The passages M are connected with the cylinders,C by valve controlled ports, these being perferably lo- 10. sage M.Within the lateral bore 1s arcated in detachable heads N-for saidcylinders. As shown in Figs. 1' and 4, the heads N engagetransversely-milled slots in the periphery of the head B and externallyconform to the contour of the latter. Each head is provided with a port0 for communicating with the end of the cylinder and atransverse bore 0which connects said port with a laterally-extending cored passage 0communicating through a port with the'pasranged a check valve P which isheld to its seatby the tension of a spring P abutting at one end againsta plug P which closes the end of the bore and at the other end against acylindrical guide portion of the valve P, loosely fitting the bore. Thusthe air which is compressed by each piston as it moves outward in thecylinder will be forced beyond the check valve P and will accumulate inthe clearance space formed by the passages L L and M. The pressure willrise with each succeeding volume which is compressed, and as theclearance'volume is small the resistance will rapidly rise until itbalances the load.

To render the operation of each piston more efiective, I have provided,first, means for utilizing the suction as well as the compressionstroke; and second, means for placing against the piston at thebeginning of its compression stroke the full accumulated pressure of theair previously stored. The first effect is produced by locating theinlet port for the cylinder adjacent to the'end of the suction stroke orinward limit of movement, and as shown, a port Q is provided for eachcylinder which communicates with the crank chamber G. The second effectis produced by means for unseating each of the valves P at the beginningof the compression stroke of each piston just after said piston haspassed the port Q, so as to close the same.

For unseating the valves P, valve rods R are arranged in bores which arealined with the bores O and extend outward from the opposite side of thehead B. The rods B have portions which closely fit the bore and aregrooved at R to hold a sealing and 111- bricating fluid which preventsleakage of air. Each rod is also provided with a sealing shoulder Rwhich in normal position engages a seat forming a complete air seal.

Near the outer ends of the rods R are springs S which are arranged incounter bores and bear against collars S on the rods,

the tension of the spring acting to hold the shoulder R to its seat. Tare rock-shafts extending in a substantially radial direction across oneend of the head B, their outer ends being provided with rock-arms Tadapted to engage with the rods R. The inner ends of these rock-shaftshave secured thereto the rock-arms T which extend substantially parallelto the shaft E- and carry memes at their free ends anti-friction rollersT These rollers engage a cam U which is sleeved upon the shaft E so asto rotate therewith, and the cam is so fashioned as to engage with theroller T once in each revolution, rocking the arm T shaft T and arm T,and moving the rod R inward against the tension of the spring S, so asto unseat the valve P. The timlng of the parts is such that this valveis unseated just after the piston has closed the port Q, as beforedescribed, and consequently the full pressure of theaccumulated volumeof compressed air will operate against the piston during substantiallyits complete compression stroke.

Whenever the clutch is released, it is necessary to exhaust theaccumulated compressed air and also to vent the cylinders during thecompression and suction strokes of the pistons by simultaneouslyunseating the valves P. The exhausting of the compressed air Will thentake place through the ports Q, as the pistons complete their suctionstrokes, while on the compression strokes the cylinders will vent to thespaces M and L L. This is accomplished by providing the cam U With anadjacent, annular, tapering portion U and by also providing means forshifting the sleeve longitudi tached to a hollow sleeve V within whichis arranged'a spring V surrounding the shaft and abutting at one endagainst the collar W fixed to said shaft. The sleeve V is grooved toreceive a non-rotating collar V, which may be connected by any suitablemechanism, not shown, to the clutch-releasin pedal.

n operation, when motion is first communicated to the shaft A it willcause the rotation of the head B carrying with it the cylinders andpistons. If the driven shaft E is under load it will remain stationary,thereby causingvthe crank F to actuate the pitman rods H and pistons Din each of the revolving cylinders. Each suction stroke of the pistonwill cause a vacuum and thereby introduce the resistance of atmosphericpres- Sure, while each compression stroke will compress the volume ofair in the cylinder and force it past the check valve P into theclearance spaces M and L L. At the start the air in the cylinder and inthe clearance space is at atmospheric pressure, but as each volume ofair is compressed and introduced into the clearance space, the pressurenecessary to take care-of a given maximum loadv may becorrespondinglyreduced.

To release theclutch, the sleeve V is moved longitudinally, causing theannular portion U of the cam to simultaneously raise all of the valves Pfrom their seats, which 'will exhaust the'accumulated compressed air andvent eacli of thecylinders, so as to interpose no resistance to themovement of the piston.

During the rapid rotation of the clutch the lubricating oil for thepistons within the cylinders will be thrown outward to a greater or lessextent by centrifugal action andwould tend to accumulate in the ends ofthe cylinders if the latter were perfectly square.

This might form an obstruction to thefull stroke of the piston, andIhave therefore avoided the difficulty by so shaping the ports in theheads of the cylinders to form drain channels for the oil. Thus as shownin Fig. 1, the ports 0 are inclined from the periphery of the cylindertoward the center, so that any oil thrown to the end of the. cylinderwill drain through this port into the transverse bore -O or out of. thepath of the piston.

What I claim as my invention is 1. In a pneumatic clutch, thecombination with a drive and a driven member,'of air compression meansinterposed between said members,.a storage for receiving and holding thecompressed air, and means for placing the cumulative pressure of saidstorage upon said air compression means during the initial portion ofeach compression stroke.

2. In a pneumatic clutch, the combination with the drive and a drivenmember, of air compression means interposed between said members, havingalternating compression and suction strokes, a storage for receiving andholding the compressed air, and means for admitting the air to becompressed into said compression means at the end of the suction strokeand for placing the cumulative pressure of said storage upon said com-'pression means during the initial portion of the compression stroke.

3. In a pneumatic clutch, the combination with rotary drive and drivenmembers, of a radially arranged air compressor connected to be actuatedby a relative movement of said members, a valve controlling saidcompressor located at the outer end thereof and movable transverse tothe plane of rotation, means automatically operating the valve in timedrelation to the relative rotation of the drive and driven members, andmeans forpheric air to be compressed and during the initial portionofthe compression stroke.*

5.- In a pneumatic clutch,- the combination with a drive and a drivenmember, of air compression means interposed therebetween and havingalternating suction and compression strokes, a storage for receiving andholding the cumulative Pressure of successive compression-strokes, meansfor delaying the admission of atmospheric air during the suction stroketo oppose atmospheric resistance thereto, and means for placing thecumulative pressure of said storage upon said compression means duringthe initial operation of each compression stroke.

6. A pneumatic clutch, comprising a drive and a driven member, a seriesof reciprocatory air compressors operated 'by a relative movement ofsaid drive and driven members, a storage for receiving and holding thesuccessively compressed volumes of air,.

arranged air compression cylinders mounted upon said head, pistons in'said cylinders, a crank upon the other of said shafts to which saidpistons are connected, check valves controlling communicating passagesbetween each of said cylinders and said air storage, and means forautomatically opening said valves successively and during the initialportion of the compression stroke of their.

respective pistons.

8. A pneumatic clutch, comprising alined drive and driven shafts, a headforming a fly-wheel for said drive shaft, provided with a series ofradially-arranged cylinders and chambered to form a limited air storage,pistons in said cylinders, a crank on said driven shaft, pitman rodsconnecting said pistons with said crank, check valves controllingpassages between the respective cylinders and said air storage, meansfor automatically opening said valves successively during the initialportion of the compression stroke of the corresponding piston, andmanually-operable means for simultaneously opening all of said valves tovent said air storage and cylinders.

9. In a pneumatic clutch, the combination with rotary drive and drivenmembers, of

a radially arranged air compressor con nected to be actuated by arelative movement of said members, a valve controllin said compressorlocated at. the outer end thereof and movable transverse to the plane ofrotation, a sliding cam mounted to be rotated by one of said members, amechanism actuated by said cam normally operating said valve in timedrelation to the relative the compressed air, a check valve controllingcommunication between said storage and air compressor, and automaticmeans for opening said valve during the initial portion of eachcompression stroke.-

11. In a pneumatic clutch, the combination with rotary drive and drivenmembers, of an interposed radially-arranged reciprocatory aircompressor, a valve for controlling said compressor arranged at theouter end thereof, an actuating member for said valve located near theaxis of said rotary members. and movable longitudinally thereof, and arock shaft having rock-arms thereon for transmitting movement from saidactuating member to said valve.

12. In a pneumatic clutch, the combination with alined drive and drivenshafts, of a rotary head mounted on one of said shafts having a seriesof radially-arranged air compressors operated by the relative movementof said shafts, valves for controlling said compressors located at theperiphery of said head, an actuating member for said valves sleevedabout one of said shafts and movable longitudinally thereof, rock-shaftsextending substantially in a radial direction having rock-arms forengaging said actuating member and oppositely extending rock-arms foractuating said valves, and rods extending transverse to the plane ofrotation arranged intermediate the latter rock-arms and said valves.

13. In a pneumatic clutch, the combination with a drive and drivenmember, of an interposed reciprocatory air compressor, havingalternating suction and compression strokes, and means for delaying theadmission of air to said air compression means until the completion ofeach suction stroke to interpose atmospheric resistance thereto.

14. In a pneumatic clutch, the combination with rotary drive and drivenmembers, of a radially-arranged air compressor actuated by a relativemovement of said members, .a ported head for the outer end of saidcompressor having transversely-extending, alined bores, a check valve inone of said bores controlling the ports of said head, and an actuatingrod extending out from said head through the alined bore, having anormally seated sealing shoulder for preventing leakage of air.

15. In a pneumatic clutch, the combinecating oil thrown outward bycentrifugalaction, therebypreventing accumulation of oil in the path ofthe piston.

16. In a pneumatic clutch, the combination with rotary drive and drivenmembers, of a radially, arranged air compressor connected to be actuatedby the relative movement of said members and comprising a cylinder andpiston therein, and means for draining the lubricating oil thrownoutward by centrifugal action to the end of said cylinder to preventobstruction of said piston.

17. In a pneumatic clutch, the combination with a drive and a drivenmember, of an interposed reciprocatory air compressor, havingalternating suction and compression strokes, a storage for receiving andholding the compressed air, a check valve controlling communicationbetween said storageand air compressor, automatic means for opening saidvalve during the initial. portion of the compression stroke, and meansfor manually controlling said valve.

18. In a pneumatic clutch, the combination with a drive and a drivenmember, of an interposed air compressor comprising a plurality of radialcylinders mounted rigidly upon one of said shafts, pistons in saidcylinders, a crank upon the other shaft, pitman rods connecting. saidpistons with said crank, a storage for receiving and holding thecompressed air, check valves controlling passages between the respectivecylinders and said air storage, means for automatically opening saidvalves successively during the initial portion of the compressionstrokes Of'the corresponding pistons, and manually operable means forsimultaneously opening all of said valves.

19. In a pneumatic clutch, the combination with a head or casing,comprising a plurality of cylinders radially mounted besaid compressorlocated at the outer end thereof and movable transverse to the plane ofrotation, and means automatically operating the valve in timed relationto the relative rotation of the drive and driven mem- 10 bers.

In testimony whereof I afiix my signature inpresence of two wltnesses.

JOHN SPRINGER.

Witnesses:

' JAMES P. BARRY,

HENRIETTA E. BOWMAN.

